The present invention relates to an electrical installation comprising several modules, preferably a modular programmable controller, whose preferably encapsulated modules are able to be electrically interconnected via bus units.
The U.S. Pat. No. 4,477,862 discloses an installation, wherein the backplane bus units are integrated in a modular subrack, so that the subracks have to be mounted individually on a wall, for example. One problem with this device is that removing individual modules of the backplane bus as needed from the assembled backplane bus is not possible. Moreover, the width of the modules must conform with the width of the subrack.
The object of the present invention is to produce an installation of several modules which minimizes the basic expenditure for the bus connection, in which the individual modules can have differing widths, in which modules located between other modules may be easily replaced, and in which the bus connection follows automatically when the modules are plugged in or pivoted on to a carrier even without a preassembled backplane bus. The present invention also seeks the ability to add modules later.